Back assembly



FIG. 1 is a perspective view of a back assembly on a stool showing atop, a back and a left side.

FIG. 2 is another perspective view of the back assembly of FIG. 1showing a front, the top and the left side.

FIG. 3 is left side elevational view, the right side being a mirrorimage.

FIG. 4 is a rear elevational view.

FIG. 5 is a top plan view

FIG. 6 is a front elevational view; and,

FIG. 7 is a bottom plan view.

The broken line showings of an actuator and a mounting portion form nopart of the claimed design. The broken line showing of a portion of thestool illustrates the environment of the claimed design and forms nopart thereof.

CLAIM We claim the ornamental design for a back assembly, as shown anddescribed.